Method and apparatus for contouring elongated metal stock while under tension



July 6, 1948. c. J. BATH A METHOD AND APPARATUS FOR CONTOURING ELONGATED METAL STOCK WHILE UNDER TENSION 4 Shgts-Sheet 1 Filed 001;. 5, 1946 INVENTORY (YR/1. J. BA TH r Arron/W576- y 1948- c. J. BATH 4 2,444,719

METHOD AND APPARATUS FOR CONTOURING ELONG-ATED METAL STOCK WHILE UNDER TENSION Filed Oct. 5, 1946 4 Sheets-Sheet 2 INVENTOR.

CYR/L J. 5/] TH H ITOENEYS C. J BATH METHOD AND APPARATUS FOR CONTOURING ELONGATED July 6,1948

METAL sTocK WHILE UNDER TENSION 4 Sheets-Sheet 3 Filed Oct. 5, 1946 m @ww iNVENTOR. Q

- CYR/L JBATH C. J. BATH METHOD AND APPARATUS FOR CONTOURING ELONGATED I METAL STOCK WHILE UNDER TENSION 4 Sheets-Sheet 4 Filed Oct. 5, 1946 JNVENfORQ cvR L J. BAT/l 1 [M015 6 Y E M 2 o W A Patented July 6, 1948 i UNITED STATES PATENT OFFICE METHOD. AND APPARATUS FOR CONTOUR- ING ELONGATED METAL STOCK UNDER TENSION Cyril J. Bath, Cleveland, Ohio Application October 5, 194.6, Serial No. 701,602

6 Claims. 1

This invention relates to amethod and apparatus for contouring elongated metal stock.

' One of the principal objects of the present invention is to provide a method and a forming machine for forming elongated members or stock, such'as sheet metal strips, rods, angles, channels, and the like, into serpentine or irregular shapes in which adjacent portions of the metal are reversely curved or bent with respect to each other.

-Another object is to form such stock about dies while'maintaining it under tension sufficient to cause'the metal to yield and lay onto the dies and take a permanent set while the stock is held by thedies in the form desired so that springing back of the metal with resulting inaccuracies in the finished article is eliminated and more uniform and consistent production of articles of greater accuracy is obtained.

Another object is to adapt a contouring machine of the general type disclosed in my copending application Serial No. 522,700, filed February 1'7, 1944, to accomplish the above objects by arranging a pluralit of dies on the rotatable support thereof so that they can be properly placed in operating position selectively from a position out of the path of swinging movement of the stock across the support, resulting from the normal cooperation of the support and tensioning means of the machine.

-Another object is to contour elongated stock material by anchoring an end thereof, applying tension to the other end to stress the metal almost to its elastic'limit, swing the stock about its anchored end While maintaining it under tension and. between reversals in the direction of swing of the stock, disposing die blocks, one at each reversal, in the path of swing progressively from the anchored end toward the other end.

Other objects and advantages will become apparent from the following description wherein reference is made to the drawings in which:

Fig. 1 is a topplan view of an apparatus embodying the principles of the present invention;

' Fig. 2 is a perspective view of a portion of the apparatus illustrating the position of the parts in forming the first bend in the stock;

Figs. 3- and 4 are perspective views, similar to Fig. 2, illustrating the different successive positions of the apparatus for forming the stock intoa serpentine shape.

"Referring to the drawings: The machine comprises a housing I on which adie carrying table or support 2 is mounted for rotation about a fixed vertical axis. The table 2 'carriesa coaxial-ring gear 3 which is driven by a cooperating gear 4 for rotating the table 2 in reverse directions; The gear 4 is mounted on a suitableshaft 5 which is supported in the housing l and in turn is rotatably driven through any suitable reversible variable speed transmission'fi by a suitable motor I, the transmission and motor being located in the housing I. The motor is controlled by a switch 8 and the transmission by a control lever 9, both of which are readily accessible to the operator.

A clamp I0, operated by a lever I l is detachably secured in the desired position on the table 2 for clamping one end of a length of stock to be formed, indicated generally at S, and for securing the end in fixed relation to the table.

The tension applying means may comprise a hydraulic cylinder [2 and cooperating piston l3 which are connected in a hydraulic system to a suitable source of hydraulic fluid by the usual reversible valve. For the present purpose, however, the fiuid pressure is applied to yieldably urge the piston lengthwise of the cylinder away from the table under the preselected pressure required to tension the stock to a high degree, preferably just below its elastic limit.

For mounting the cylinder l2 for adjustment toward and away from the table and for free swinging movement about an axis parallel to the axis-of the table, a sliding support M is mounted on the frame I on suitable guideways I5. A rack I6 is fixedly secured on the frame I and is engaged by a pinion H on the sliding support. A hand wheel [8 is operatively connected to the pinion for rotating the same to move the sliding support M to the desired adjusted position lengthwise of the frame I toward and away from the table.

The purpose of the sliding support I4 is to make possible the use of the apparatus with stock of different lengths. For example, a piece of stock may be of such length that the piston l3 would have to travel the length of the cylinder before the completionof the contouring operation. In such an instance, the table 2 is stopped and the hand wheel I 8 released and the fluid pressure admitted to the cylinder l2 at the left of the piston causes the'cylinder to follow up the piston in a direction toward the table while the piston remains fixed. If desired, of course, the hand wheel l8 may be operated for the purpose of advancing the cylinder toward the piston. After the cylinder is in the new position, it may be locked and the operation of the apparatus continued until anadditional portion of the length of the piece of stock being formed equal substantially to the'stroke of the piston has been suitably contoured. If, as is frequently the case, a large number of pieces of stock of the same length and requiring less travel of the piston than the length of the cylinder are to be contoured, the slide l4 can be secured in a fixed adjusted position by suitable bolts or otherwise. The rack and pinion are shown diagrammatically for clearness and illustration, it being understood that they are pref erabl of the self-locking type, usually the type employing a worm gear connection between the pinion and hand wheel. A table .26 is mounted on the support M for free rotation about an up right axis, such as the shaft 2!, in all'positions of the support 14.

The table 20 has a horizontal slidewayiniwhich a slide 22 is mounted for reciprocationinalineal horizontal path. The slide '22 carries a clamp or gripper 23 operable by a handle 24. The-gripper 23 is mounted on a carrier 25 which is adjustable vertically in .a guide 26 of an upright support 2-! on and rigid with the slide 22. The support 21, and through it the gripper 23,;is connected to thepiston 13 so as to be yieldably opposed by the piston-when thegripper 23 is pulled toward the table by the stock being contoured.

The structure thus far described is more fully disclosed in my above identified-application and comprises. the more basic machine with which the dies and die operating means are combined to provide the present invention.

.As more fully-setforth inmy copending application, a length of stock may be contoured .by securing one end in the clamp l and the other end in the clamp-or gripper 23 and then applying tension thereto by means of the :piston 13. With a suitable-die on the'table 8, the table is rotated-so as to lay the 'tensioned stock S onto=the die, the tension being maintained just below the elastic limit of the stock. Thisis possiblebecause of the free swinging action of the cylinder [2 about an upright axis parallel to the axis of the table ,andto the fact that-the piston is yieldably movable endwise as the stock shortens .in overall length during contouring. but the piston maintains the required tension-during the contouring operation. With a length-of stock S secured at one endtothe clamp or anchoragel 0 and secured at the other end to the clamp 23 of the piston 13, fluidpressure is admitted into the cylinder -l2.to the left of the piston in the Fig. 1 so as to provide the required'yieldable gessureand thereupon the table is rotated to lay .the stock-on the die. For purposes of illustration in the present invention the table 2 is shown as carrying three separate dies for producingadouble reversecurve in the stock, it being apparent that any number of such dies may be employed depending-on the final contour desired in the finished product. These dies, designated 38, 3| and 32, respectively, are

arranged so thatwhen they are in operating position on the table'they define a serpentine path for the stock. Due to the swingor sweep-of the stock about the pivotal axis of thecylinder l2 as the table is rotated, it is apparent that -;the dies 1 cannot be maintained fixedly in the position :in which they are to operate. Accordingly, each one of the dies is independently movableintoand out ofthe path of swing of the stock and meansare carried by thetable for anchoring thedies. against which is accomplished by rotating the table in a clockwise direction. During this operation the path of swing of the stock is unobstructed by the dies 3| and 32, both of them having been previously moved out of position. When the stock S has been laid on the desired portion of the surface of the die 30, at which time the stock has swung to the right in Fig. 2 beyond theoperating position of the die 3|, the die 3| is moved into operating positions and anchored, as illustrated in Fig. 3. Thereupon the table is reversed and driven counter-clockwise and the stock is laid on the die 3|. The-counter-clockwise rotation of the table 2 for laying the stock on the die 3| continues until it is laidon the desired forming surface of the .die.3l at which time the stock has swung to the left beyond the operating position of the die 32. When the stock passes this position, the die 32 is moved into operating position within the path of swing of the stock. Thereupon the tableisreversed and driven in a clockwise direction as illustrated in Fig. 4 thus laying thestock on the required portion of the forming surface of .thedie 32. In this manner, starting adjacent the point of anchorage afforded by the clamp 10, the metal stock, while maintained under the required ten-, sion, is swung to and fro bysuccessive reversals in the direction of rotation of the table 2 and at the end of each rotation a die block is dropped into the path of swing, this operation progressing from the anchorage of the clamp l0 toward the swinging end of the stock which is held by the gripper orclamp 23.

Inorder to mount the dies 30, 3I' and 32 for manipulation in this manner, the following arrangement has been found satisfactory.

Referring first to the die 30, since the table can be rotated so that this-die will not obstruct the path of swing when the stock is insertedgthe die 39 is mounted on suitable blocks 33 which arosecured in fixed position on the table 2 and support the die 38 in spaced relation thereahove.

The die 3i, as best illustrated in Fig. 3, is pivotally mounted at one of its ends on a block which is secured in fixed relation to the top of the table beyondthe path of swing of the stock and permits swinging of the die 3| about its pivoted end-laterally into and out of operating position. An operating lever 35 is secured to the die 3| for swinging the die into andout of the operating position within a path of swing of the stock. In order to secure the die 3! in the-operating position, a detent36 is fixedly mounted ,on the table and engages an edgeof the lever when the lever is moved to the properposition-so as to lock it, and thereby .the die 3|, in said position. .The lever 35 is released by lifting its outer end clear of the detent 36.

The die 32, on the other hand, is supported'for movement toward and away from the plane of the table so as to be movable into and out-of operating position .witlrrespect to the path of swing of the stock. For this purpose an upright support 31 is secured on the table in fixed position and a lever 38is pivoted betweenits endsto-the support 3.1 by-a horizontal pivotforverticalrocking movement. ,A suitable link :39 isconnected'at one end to one end of the lever 3! and atzthe other -1 end'to the die 32 An overbalance 40 is carried 23 of the piston at theotherend. The die 30 15 disposed in a ,position' ,for making .the first bend on the opposite end of the lever 3,8.andnormally raises the die 32 to-a position above the path of swing of the stockandholdsit in-said position. The die is provided with two dependent pins M which, when the die is lowered bya downward movement. of: the lever 38 in opposition to the overbalance, engage in suitable sockets 42 in blocks 43 which latter are secured in fixed position on the table.

As shown in the drawings, the clamp I0 and the clamp 23 are adjustable vertically and these are set so that the stock clears the top surfaces of the blocks 33 and 43.

In operation the table is rotated clockwise and the stock is first formed around the die 30. The die 3| is moved in place and locked. Thereupon the table is reversed to form the stock about the die 3|, the die 3| remaining locked in operating position. The lever 38 is operated by the operator of the machine to move the die 32 into position on the table and anchor it in operating position by engagement of the pins 4] in the sockets 42, and then the table is reversed again.

A suitable gage 44 may be carried on the last die, which in the illustrative form is the die 32. This gage is positioned so as to engage the stock when it has been formed to the required degree about the die 32 at which time the table is, stopped and the stock unclamped and removed.

By means of the relatively simple elements described a large number of dies positioned to give a large number of difierent contours may be arranged on a single table and used for forming the stock in the manner described.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the claims or the equivalent of such be employed.

I therefore particularly point out and distinctly claim as my invention:

1. The method of contouring elongated metal stock comprising anchoring one end of the stock, continuously applying tension to the entire length of the stock and concurrently repeatedly swinging the stock from one end transversely of its length across a predetermined path while maintaining the stock under tension, and interposing die blocks one at a time alternately on opposite sides of the stock progressively from the point of anchorage toward the opposite end of the stock in the path of swinging movement of the stock between reversals in the direction of swing'of the stock, and maintaining all of the die blocks between the point of anchorage and the last inserted die block in fixed contact relation to the stock.

2. The method according to claim 1 characterized in that the tension applied to the stock is suflicient to stress the stock to about the elastic limit thereof.

3. The combination with a contouring machine including a rotatable table, a clamp thereon adapted to engage one end of a length of stock, means to rotate the table reversely, selectively, a tension gripper adapted to be connected to the other end of a length of stock, means supporting the gripper for movement toward and away from the table and for concurrent swinging movement about an axis parallel to the axis of the table, means to yieldably urge the gripper away from the table to tension a length of stock held between the gripper and clamp, a row of dies on the table defining a serpentine path for the said stock which path lies in the plane of sweep of the stock, means carried by the table and normally supporting the dies, respectively, out of said path of sweep and for movement into said path, selectively, and means to hold the dies accurately in position when they are moved into said path.

4. In a contouring device, a support, a plurality of dies thereon defining in one position a serpentine path for stock to be contoured therebetween, means for tensioning the stock and concurrently swinging the stock transversely of and laterally beyond the said path in opposite directions successively, means supporting the dies individually for selective movement into and out of the path of the swinging stock, means on the support operatively detachably engageable with the dies, respectively, for securing the dies in said one position, selectively, when the dies are moved into said position.

5. In a contouring device, a support, a plurality of dies thereon defining in one position a serpentine path for stock to be contoured therebetween, means for tensioning the stock and concurrently swinging the stock transversely of and laterally beyond the said path in opposite directions successively, means on the support to grip one end of stock, means cooperable with the support for gripping the other end of the stock and tensioning the stock and swinging the stock to and fro across the said serpentine path, means on the support suspending one of said dies above its operating position out of and above the path of swinging of said stock, and operable to lower said one of the dies into its operating position wherein it intersects said path of swing, and means on the support operative to engage and hold the said one die in position when it is lowered into position.

6. In a contouring device, a support, a plurality of dies thereon defining in one position a serpentine path for stock to be contoured therebetween, means for tensioning the stock and concurrently swinging the stock transversely of and laterally beyond the said path in opposite directions successively, means on the support to grip one end of stock, means cooperable with the support for gripping the other end of the stock and tensioning the stock and swinging the stock to and fro across the said serpentine path, means on the support connected to one of the dies and supporting the said one die for movement transversely of said path to an idle position outwardly beyond the limit of swing of said stock, means operably connected to said one die and to the support and operable to swing the die from said idle position into operating position in said path and to latch the die in said operating position.

CYRIL J. BATH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 898,424 Bartlett Sept. 15, 1908 983,664 Wilson Feb. 7, 1911 1,264,248 Yoder Apr. 30, 1918 1,354,770 Little Oct. 5, 1920 1,968,010 Bailey July 31, 1934 2,190,821 Broomhan Feb. 20, 1940 2,275,619 Enberg Mar. 10, 1942 2,331,294 Bank et a1. Oct. 12, 1943 2,411,801 Nielsen Nov. 26, 1946 FOREIGN PATENTS Number Country Date 190,361 Great Britain Dec. 21, 1922 494,702 Germany Mar. 27, 1930 

